In plants, pathogen attacks invoke multiple layers of host immune responses. Many pathogens of plants and animals deliver effectors into host cells to suppress host immunity, and many plants have evolved resistance proteins to recognize effectors and trigger robust resistance.
Botrytis cinerea is a fungal pathogen that infects almost all vegetable and fruit crops and annually causes $10-100 billion losses worldwide. With its broad host range, B. cinerea is a useful model for studying the pathogenicity of aggressive fungal pathogens.